October 2012

Come on, whoopers!

For the first time in more than a century, whooping cranes,
the most endangered of the world's 15 species of cranes,
are migrating in Wisconsin skies.

This is a cutting-edge species recovery project, described by one U.S. Fish and Wildlife Service (USFWS) official as, "the wildlife equivalent of putting a man on the moon."

One of the most daunting challenges was teaching captive- raised cranes to migrate. But the first challenge was to save the "whoopers" from oblivion.

One of two crane species native to North America, whoopers were never as abundant as sandhill cranes. Hunting and habitat loss reduced their numbers drastically. By 1946, there were just 16 whoopers wintering at Aransas National Wildlife Refuge (NWR) on the Texas Gulf Coast – the last wild whooping cranes on earth.

With federal protection and management, the species began to recover. By 1958, there were 32 cranes at Aransas, including nine new fledglings. But droughts and diseases, storms, power lines and illegal hunting all took their toll.

A recovery program is born

In 1967, the USFWS began a whooping crane recovery program at the Patuxent Wildlife Research Center (WRC) in Laurel, Md. There were three goals: study the birds in the wild, breed them in captivity and return captive-raised eggs or birds to the wild.

By 1975, Patuxent had a successful captive breeding program and the wild population was growing. In 1975, 49 wild whoopers, including eight new fledglings, made the 2,500-mile migration from Canada's Wood Buffalo National Park to Aransas NWR.

Having all the wild whoopers in one flock made the species too vulnerable. But creating a new flock from scratch presented a major obstacle: migration. Cranes, like many other precocial birds, have an instinctive urge to migrate, but they learn when and where from their parents. A new flock of captive-raised chicks would have no adult cranes to show the way.

One possible solution was to use wild sandhill cranes as "foster parents." Sandhill cranes were abundant and captive sandhills had served as foster parents in Patuxent's breeding program. Raised by wild sandhills, the whoopers would (the biologists hoped) grow up wild. They would learn a new migration route from Idaho to New Mexico. And they would produce little whoopers and build a new flock.

From 1975 through 1989, USFWS biologists placed 287 whooping crane eggs from Patuxent into wild sandhill nests at Grays Lake; 210 hatched and 85 chicks fledged, and they all migrated to New Mexico and back with the wild cranes.

As the whoopers reached sexual maturity at Grays Lake, the males seemed to have the right nesting instincts, but their courtships were aimed at sandhill females and both sides quickly lost interest. The female whoopers at Grays Lake had no males of either species courting them and they showed no interest in nesting. As the Grays Lake project ended in 1989, the Aransas flock had grown to 146 cranes, after six good breeding years. But the single wild flock was still all too vulnerable to natural or manmade disasters.

A film gets ideas flying

In 1989, Canadian wildlife sculptor William Lishman produced a documentary called "C'mon Geese." It told the story of teaching Canada geese to follow his ultralight. That July, at the Experimental Aircraft Association fly-in at Oshkosh, Terry Kohler, a Wisconsin businessman and conservationist, saw the video. Returning home, he called his friend George Archibald at the International Crane Foundation. Did Archibald think it was possible, Kohler asked, that whoopers could be taught to migrate behind an ultralight piloted by a human?

"I ignored George's horrific laughter," Kohler later wrote, "and I sent him the video."

A few months later, Archibald brought up the idea at a meeting of the International Whooping Crane Recovery Team, a coalition of U.S. and Canadian wildlife experts and officials. To Archibald's surprise, team members were intrigued by it.

But the recovery team moved slowly on the idea and it was 1995 before rancher/ biologist Kent Clegg convinced them to let him lead young sandhill cranes on migration. Clegg had worked at Grays Lake; he had heard of Lishman's work, and was thinking along similar lines.

Two years before, Lishman and partner Joe Duff used ultralights to lead a flock of 18 young geese on their first migration from Ontario to Virginia – the first human-led migration. The following spring, 13 of the "honkers" returned on their own to Ontario.

In the spring of 1995, 20 captive sandhills hatched at Clegg's Idaho ranch. Clegg allowed them to imprint on him just enough so they would follow him but not enough to depend on him. By October, the chicks were following his ultralight on flights of 25 miles or more around the ranch. On Oct. 15, Clegg led 11 sandhill cranes away from the ranch on the world's first ultralight-led crane migration.

From Grace, Idaho to Bosque del Apache NWR near Socorro, N.M., the migration covered 748 miles. It took 11 days. One bird returned to the ranch. Two were killed by golden eagles. One was grounded by a respiratory ailment. On Oct. 26, the ultralight and seven sandhills landed at Bosque del Apache. When Clegg and the ultralight disappeared, the birds joined a large flock of wild sandhill cranes.

Over the winter, two of Clegg's cranes were killed by hunters and one disappeared. In the spring, the four survivors migrated north with the wild cranes.

In October 1996, he led another seven captive-raised sandhill cranes on a 15- day migration to Bosque del Apache. Again, the survivors migrated north with wild cranes.

In 1997, he got the green light for a migration with whooping cranes. On Oct. 12, Clegg's ultralight left the ranch with eight sandhills and four whoopers in trail. All 12 made the nine-day flight and settled in with the wild sandhill cranes at the refuge. Over the winter, two of the whoopers disappeared. In the spring the survivors migrated north.

Dress rehearsal is over

The Whooping Crane Eastern Partnership (WCEP), an association of nine federal, state, and private agencies and organizations was formed in 1998 and began looking for sites for a new flock. Lishman and Canadian photographer Joe Duff formed Operation Migration (OM) and led a flock of sandhill chicks from Ontario to Virginia. In the spring, the birds returned on their own to Ontario. It was time to begin establishing a new and (it was hoped) permanent flock of whooping cranes east of the Mississippi.

From several possible sites, the Recovery Team chose Necedah NWR in Wisconsin as the training site and Chassahowitzka NWR near Tampa, Fla. as the wintering site. Costume rearing developed at the International Crane Foundation was modified and fine-tuned to allow pilots to wear the burkha-like crane costumes.

The migration route was 1,200 miles long and the first year was a dress rehearsal using sandhill cranes. The birds were hatched at Patuxent and, eight weeks later, were moved to Necedah. There, they learned to follow the ultralight on the ground and in the air.

On Oct. 3, 2000, the OM team took off from Necedah and headed south with a flock of 13 sandhill cranes. Riding the ultralight's wingtip vortices, the birds mostly glided, flapping their wings very little. Two or three birds traded off the point position less than a foot behind the ultralight's wing.

A typical day's flight lasted 60 to 90 minutes and covered anywhere from 20 to 80 miles. On Nov. 8, the birds reached Chassahowitzka, where they spent the winter loafing around their pen and the nearby meadows.

On Feb. 25, 2001, 10 of the 11 cranes left the pen unexpectedly and disappeared. The last bird hung around "Chazz" until April 17, and then headed north. On April 27, a volunteer at Necedah picked up radio signals from all 11 birds. The next day they landed near the training pen.

The "dress rehearsal" was over. The sandhill cranes had left their wintering grounds on their own initiative and had returned to the place where they fledged, though no one knew what they had been up to for 62 days. And they were wary of humans; OM's methods to promote wildness appeared to be working.

In a class of their own

The "Class of 2001" – 10 whooper chicks – hatched at Patuxent, and in July, Terry Kohler's Cessna Caravan brought them to Necedah. After a few days' rest, the chicks were led out to the grass runway next to their pen and began running back and forth behind the ultralight. By early August, they were following it on short flights around the refuge.

On Oct. 17, three ultralights and eight birds took off southbound. Bad weather plagued the project with only six flying days between Oct. 17 and Nov. 4.

Finally, on Dec. 3, 2001, the ultralights landed at the Homosassa pen in Citrus County, near Chassahowitzka NWR, with six whooping cranes flying right behind them and a seventh crane riding in the trailer. The eighth bird had died after colliding with a power line. Two days later, they were moved to their isolated winter pen in the refuge. Their journey had taken 48 days, 22 of them spent grounded by weather.

The young whoopers settled in for the winter, foraging outside their pen during the day and spending their nights inside the protective enclosure. Two were lost to bobcats. On April 10, the five surviving whoopers left the refuge and flew north, tracked by ground vehicles. Nine days later, four whooping cranes landed at Necedah NWR, close to their training pen. The fifth bird, a female, wandered around southern Wisconsin for two weeks. Then she too returned to the refuge. In future seasons, she and her "classmates" migrated south and north on their own. For the first time in more than a century, wild whooping cranes migrated in eastern skies.

Every Autumn since then, Operation Migration has led a flock of young whoopers on their first migration. And every spring, the birds return on their own, wild and free. The eastern flock now numbers about 100 birds and has produced several chicks, the first in 2006. WCEP's goal is a flock of 125 birds with 25 successful nesting pairs.

The Aransas-Wood Buffalo flock now has about 250 birds, though drought and water use issues in Texas may threaten its long-term survival. Including the captive breeding programs, the world population of whooping cranes today is just over 500 birds.

Weather continues to bedevil the migration project. The 2001 migration of 48 days turned out to be one of the shortest – the longest nearly 100 days, with weather being the main culprit. In February 2007, a storm surge struck the pen at Chassahowitzka, killing 17 of the 18 chicks that had arrived only days before. And although the flock has produced chicks at Necedah, in recent years, whooper parents have abandoned many of their nests there, probably because of black flies that drive the parents off the nests and leave the eggs prey to eagles and other predators.

In 2011, the training site was moved from Necedah to the Wisconsin DNR's White River Marsh State Wildlife Area in Green Lake County. The move avoids the black flies and creates a new and separate nesting area for the cranes introduced in future years.

And WCEP has added a new technique to bolster the eastern flock. "Direct Autumn Release" (DAR) places captive-raised chicks among wild cranes at Necedah and at Horicon Marsh. Most of the DAR birds have joined the flock and followed wild cranes on migration.

Why do we bother?

Reintroducing whooping cranes to the eastern United States is difficult, demanding, uncertain and expensive. But the whooper has become an icon of wildlife conservation, drawing public attention and private and corporate contributions to the plight of many endangered species. Moreover, saving the cranes requires that we restore and protect the precious wetlands on which so many species depend, including ourselves.

Ornithologist Roger Tory Peterson wrote, "Birds are indicators of the environment. If they're in trouble, we know we'll soon be in trouble."

Naturalist John Muir may have said it best: "Tug on anything at all and you'll find it connected to everything else in the universe."

David Sakrison serves on the board of directors of Operation Migration.